Hi,

It is a Trane Unit, made in 1994, it starts, but does not last, for more than few minutes.

I understood that the problem is to clean the heat sensor, but I could not find it.

Any clue where is that sensor.

On one side of the burner assembly, usually opposite the igniter, and will be directly in the flame when burners are fired. Cleaning the flame senser is the best place to start. But don't try doing it with it in place because you just really can't do a good enough job without taking the flame senser out and cleaning it thoroughly with steel wool, sand cloth , or fine sand paper. If you can post a few clear pics of the burner area, we should be able to locate it for you.

Thank you for the reply.

Unfortunately, there is nothing like that at all. My heater has 2 burners only, one has the igniter and the other one has nothing at all. I suspect another location, that it is on a higher location of the burner and in the center, but not reachable, it has PO3 on it. I'm not sure that this is the sensor.
Is it possible that the igniter same as the sensor or integrated in the same part?


Thank you,

Yes, it sure is very possible. Im not all that familiar with Trane, but I know some manufactures did this. May have to contact a train dealer and ask them. Meanwhile, Ill see what I can find.

All else fails have a good flash light and follow all wires, pairs of wires, and may even be a single wire and use ground for the other connection.
The above is general information, may not apply.

Thank you for the reply,



Here is few numbers and some photos.

Model # TUE040A924A1

Seial # J40504676

ANS Z21.47A-1990

Photos 26, 28, 43 and 44 show the ignitor and a black box which I suspect to be the flame sensor.

Photos 29, 37 and 41 show what I highly doubt to be the flame sensor. The plugs go above the burners and to the senter.



Please let me know your input.

More photos

Well, you got me. Ive never seen that setup before. The glow plug, yes. The box that the glow plug mounts to, no. Sorry, I just don't think I can be of much help on this one. What does it call the box on the wiring diagram?

Actually I took the piece a part and went to nearby parts shop and he said that the black box is the flame sensor, and it was probably made for Trane only. He did some search but could not find a part for me.
I need to call trane and see if they can provide it.

Try these people as well:
Cooling & Heating (http://marcone.com/HeatingCooling.aspx)

Please let us know what you find.